How to serialize java.math.BigDecimal in Avro?

Here is the code :

"type": [ {
    "type": "string",
    "java-class": "java.math.BigDecimal"
 } ]

Avro introduced logical types in 1.7.7 (I believe) that should help you serialize decimal.

https://avro.apache.org/docs/1.8.1/spec.html#Decimal